#!/usr/bin/env python
#coding:utf-8

import math

print math.atan( 1 )  / math.pi, 'pi'
print ( math.atan( -1 ) + math.pi ) / math.pi, 'pi'
print math.atan(0)    / math.pi, 'pi'
print math.atan(1000000000000000000000) / math.pi, 'pi'
print ( math.atan(-1000000000000000000000) + math.pi ) / math.pi, 'pi'

#atan2( y, x ) == atan( y/x ), but atan2( -1, 1 ) is -3/4 * pi
print '===='
print math.atan2( 0, 1 ) / math.pi, 'pi'
print math.atan2( 1, 1 ) / math.pi, 'pi'
print math.atan2( 1, 0 ) / math.pi, 'pi'
print math.atan2( 1, -1 ) / math.pi, 'pi'
print math.atan2( 0, -1 ) / math.pi, 'pi'
print math.atan2( -1, -1 ) / math.pi, 'pi'
    
    
